Starter device for an engine or the like

ABSTRACT

A starter for a shaft of an engine or the like including an annular member surrounding the shaft and connected to a fixed housing part through a spring. The annular member is coupled to the shaft through both a free running drive and a differential drive. The shaft is initially rotated by the force of the spring, acting through the free running drive, and the spring is loaded by shaft movement acting through the differential drive. Stop members selectively control operation of the differential drive.

D United States Patent 11113,583,379

[72] Inventors Ernst "an; [56] References Cited Heinz Eibl, bothof RllhSlOrf. Germany UNITED STATES PATENTS 3.010,443 ll/l96l Lyvers l23/l85(B-l) m] F'led 3 032 024 /1962 Furlon 123/1795 Patented June 8,1971 g [73] Assignee Motorenfabrik Hat: G.m.b.H. Primary Examiner-Mark M, Newman Ruhstorf, Germany Assistant ExaminerCort R. Flint [32] Priority Apr. 30, 1968 Attorney-Larson, Taylor & Hinds (33] Germany [31] P17512703 ABSTRACT: A starter for a shaft of an engine or the like including an annular member surrounding the shaft and con- [54] g AN ENGINE OR THE LIKE nected to a fixed housing part through a spring. The annular g member is coupled to the shaft through both a free running [52] U.S.Cl 123/185, drive and a differential drive. The shaft is initially rotated by 123/179 the force of the spring, acting through the free running drive, [5]] Int. Cl F02n 5/02 and the spring is loaded by shaft movement acting through the Field of Search l23/l differential drive. Stop members selectively control operation FR, I85 B, B-l, 1798 of the differential drive.

PATENTED JUN a 19m SHEET 1 BF 2 PATENTEDJUN 8l97| 3,5 3 379 sum 2 BF 2 STARTER DEVICE FOR AN ENGINE OR THE LIKE BACKGROUND OF THE INVENTION This invention relates to starters, and in particular it relates to a new and improved starter of the type used for starting an engine or the like.

It is known to provide spring operated starters in which the spring is reloaded to store energy by engine movement after the starting process has been completed. The previous devices of this type have been capable of performing the intended function However. there exists a continuing need for new and improved starting devices which are lighter, more reliable. more sturdy and/or more compact than previously known starter devices.

SUMMARY OF THE INVENTION Thus, a purpose ofthis invention is to provide a new and improved starter device of the type used for starting engines or the like in which the number of moving elements and the masses of the moving elements is reduced to a minimum thereby providing a starter device which is lighter, more reliable, more sturdy and/or more compact than starter devices known heretofore.

This purpose of the present invention is achieved by providing a control member connected by a spring means to a fixed housing part, the control member being coupled to the shaft to be started through both a free running drive and a differential drive. These drives selectively couple the control member and the shaft such that the starting force from the spring is transmitted to the control member and through the free running drive to the shaft; and the force to reload the spring is transmitted from the shaft through the differential drive to the control member, and hence to the spring.

According to a preferred embodiment of the invention. the control member is an annular collar surrounding the shaft and forming and annular space therebetween. The spring means may be a spiral spring mounted between the collar and the housing; and the two drives are normally located in said annular space. A bushing having a generally cylindrical outer surface is normally fixed to the shaft for rotation therewith, and the said outer surface forms the inside of the said annular space.

The free running drive of the present invention comprises an arrangement whereby relative movement between the collar and the bushing is permitted in one direction by is prevented in the opposite direction.

The differential drive comprises a plurality of rolling elements positively engaging both the bushing and the collar by suitable means such as friction, gear teeth, or the like. The rollers may be arranged in planetary fashion and spaced from each other by means of an epicyclic carrier means. In accordance with a further feature of the invention the rotational mobility of the carrier means may be controlled, thereby in turn controlling the operation of the differential drive. For example, the carrier means, which is normally permitted to rotate about the axis of the shaft and the bushing, may be prevented from rotating about said axis by a crank rod, a brake or by hand, etc. whereby rotation ofeither the collar or the bushing will cause the said rolling elements to rotate about their axes. Suitable means are also provided for holding the collar in a position whereat the spring means is in its wound or loaded position.

In accordance with a further feature of the invention engagement of the means for holding the collar in the wound spring position may be actuated either immediately after the starting process has been completed, or after a timed delay or after the shaft to be started has reached a certain speed.

Thus. it is an object of this invention to provide a new and improved starter device.

It is another object of this invention to provide a new and improved starter device for engines and the like, which device is more reliable, lighter. more sturdy and more compact than starter devices known heretofore.

It is still another object of this invention to provide a starter device of the type wherein the power source for effecting starting is automatically reloaded after completion of the starting process, said device including a free running drive and a differential drive between the spring loaded control member and the shaft to be started.

It is still another object of this invention to provide a starter device of the type described including a free running drive and a differential drive wherein reloading of the starter power source may be accomplished either automatically upon completion ofthe starting process or after a delay.

Other objects and the attendant advantages of the present invention will become apparent from the detailed description to follow together with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS There follows a detailed description of a preferred embodiment of the invention together with accompanying drawings. However, it is to be understood that these are provided only for purposes of illustration and that the invention is capable of numerous modifications and variations apparent to those skilled in the art.

FIG. 1 is a longitudinal sectional view taken through a starter device constructed in accordance with the feature of the present invention.

FIGS. Ia and lb are partial views of FIG. 1, showing certain elements in different operational positions.

FIG. 2 is a cross-Sectional view taken along line II-II of FIG. I but showing a greater vertical extent of the device than is visible in FIG. I, and partially broken away to show a partial cross section of another portion of the device.

FIG. 3 is a longitudinal sectional view similar to FIG. I but showing a modification ofthe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, like numerals represent like elements throughout the specification.

A shaft 1, which may be, for example, the crankshaft of an internal combustion engine of known construction, extends into a housing part 2 ofa starter device. On the conical end la of this shaft, a bushing 4 is rigidly attached by means of a tightening nut 3. A control member 6 in the form of an outer collar extends about the bushing 4 and is separated therefrom by means ofa roller bearing 5 permitting rotational movement of the collar 6 relative to the bushing 4. This collar 6 includes a cylindrical portion which surrounds the bushing 4 nd forms between the cylindrical portion and the bushing 4 an annular space. A spiral spring 7 surrounds the collar 6 and is connected at one end 70 to the fixed housing part 2 and a its other end 7b to the collar 6. Thus, it can be seen that turning the collar 6 relative to the fixed housing part 2 winds the spring thereby loading the same with stored energy, ad this serves as the power source of the starter device. A cover plat 8 is provided to close off the elements of the starting device to the outside.

In the annular space between the elements 4 and 6 there is provided a free running drive including a plurality of rolling elements 9 mounted between and cooperating with outer and inner surfaces and 9b, respectively. The outer surface 90 is fixed to the collar 6 while the inner surface 9b is fixed to the bushing 4. A portion of the contour of elements 90 and 9b is visible in FIG. 2. It can be seen that when the element 9:: is turned in the clockwise direction the rolling elements 9 are prevented from rolling, and hence they cause the element 9b, and hence also the bushing 4 and the shaft 1 to rotate in the clockwise direction. However, the element 9b can rotate continuously in the clockwise direction relative to the element 9a which may thus remain stationery.

Also mounted in this annular space is a differential drive comprising a plurality of rolling elements 10 which positively engage both the cylindrical outer surface of bushing 4 and a cylindrical inner surface of collar 6. The rolling elements thereby constitute a planetary epicyclic system.

The cylindrical rollers as shown in the drawings would positively engage the elements 4 and 6 by means of friction. However, it is also possible to provide the elements 4. 6 and 10 with gear teeth thereby providing a differential drive planetary gear system wherein the element 4 would constitute the sun gear, the elements 10 would constitute the planet gears and the element 6 would constitute the ring gear.

The elements 10 are spaced apart by a carrier means comprising sideplates 11 which are connected together by means of crossbars Ila extending between the rolling elements l0. A stop member 12, the purpose of which will be explained in greater detail below, is rigidly attached to a sideplate 11.

The starter device also includes a crank rod 13 which passes through an opening in the housing part 2 and is permitted to undergo longitudinal movement but is prevented from undergoing angular movement by means of a pin 14 which engages an elongated slot 13a in the crank rod 13. This crank rod also includes a circumferential groove 13b in which is engaged a leaf spring 16 for urging the crank rod 13 to the left, that is to the position as shown in FIG. 1. This leaf spring is held to the housing part 2 by means of screws 15. The crank rod 13 also includes an end 13c which engages in a notch 6a which is formed in the periphery ofa flange portion of collar 6 (see FIG. 2). The device also includes a piston 17 mounted in a chamber in the housing part 2 and connected by a restricted opening to the interior of the starter device (which may be assumed to be at atmospheric pressure). The righthand end of this piston 17 is attached to the leaf spring 16 by means of a screw 17a. Spacing of the various elements along the bushing 4 are provided by means of snap rings 18a and 18b fixed in the bushing 4 and by spacing rings 19 which position the rolling element 10 and the inner surface 9b.

The embodiment of H08. 1, 10, lb and 2 operates as follows.

To start the combustion engine the crank rod 13 is first pulled to the right until its end 13c emerges from the notch 60 of the collar 6 and is moved out to the right of the stop member 12, so that the elements 11 and 12 can rotate freely. The collar 6, therefore, is released for rotation and it moves clockwise under the effect of the loaded spring 7. The outside ring 90 in this case is driven and it drives the inside ring 9b through the rolling elements 9, and thus also the bushing in the clockwise position. The crank shaft 1, rigidly connected with the bushing 4, will also be driven in the clockwise direction and the combustion engine is started after about one revolution of the collar 6. The started engine then itself accelerates its r.p.m.

As soon as the outside ring 9a comes to a stop after the starting process of the collar 6, the inside ring 9b of the freely running mechanism, the bushing 4 and the crankshaft 1 continue to rotate with the running engine. The rollers 10 now rotate between the rotating bushing 41 and the stationary collar 6, whereby the carrier means 11 and 11a move at a decreased speed in a clockwise direction.

After this starting process, the reloading of the starting spring 7 can begin at varying times. The reloading can be started either immediately after the starting process or else after a slight delay, or only after the combustion engine has reached a certain r.p.m.

If an immediate reloading is desired, the crank rod 13, which was pulled out to the right beyond stop 12 to permit rotation of elements 6, 10, l1 and 11a to start the engine, must now be urged immediately to the left by spring 16 to assume the position shown in H6. la after the parts have started to turn. In this case it rests with its face on the face ofthe collar 6 which has just started its rotational movement. After a complete revolution of the parts in a clockwise direction during which the combustion engine will have started, the stop 12, which moves likewise in a clockwise direction with the plates 11, encounters the end 130 of crank rod 13 in the position indicated by a dash-dot line in FIG. 2. As a result, first of all, further rotational movement ofthe plates 11 and crossbars 11a in a clockwise direction is blocked, so that the friction rollers 10 can no longer revolve around the axis of the crank shaft 1. Rather, these rollers are forced by the bushing-d. which is revolving in a clockwise direction together with the running engine, into a counterclockwise rotational movement around their own axes, as a result of which the collar 6 is now caused to rotate in a counter clockwise directional movement by the rollers 10. Because of the transmission ratio Da:Dr'=-A3, selected in the case of the embodiment shown by way of an example, one will achieve, after about three revolutions of the bushing 4 in a clockwise direction (while elements 11 and 11a are stopped), one complete revolution of the collar 6 in a counter clockwise direction and, at the same time, the starting spring 7 is again fully loaded and the crank rod 13 will now snap into the notch 60 of the collar 6 under the effect of its leaf spring 16, thereby preventing further movement of collar 6. The reloading process of the starter spring 7 has now been completed. The parts 6, 9a remain stopped and only the parts 4, 9b, 10 continue to rotate with the running engine. The elements 1! and 11 a now rotate freely again, because the recess 13d ofthe crank rod 13 again permits free passage of the stop member 12.

If, on the other hand, a delayed reloading of the spring 7 is desired, then the crank rod 13 must be pulled out further to the right, as shown in H0. 117, and it must be held for a brief span of time in this position. The piston 17 in this case is likewise moved far out of chamber 2a, so that the restricted passage 2b will delay a return movement of the crank rod 13 to the left after its release. The crank rod 13 will reach the stop member 12 with its end only after a slight delay. The reloading procedure now takes place in the same manner as described above. Of course the reloading procedure can also be delayed by a hydraulic throttle instead of by means of the restricted air passage 2b.

In another embodiment, as shown in FIG. 3, a centrifugal governor may also be used to delay reloading of the spring until a certain shaft speed has been attained. The arrangement of the starter spring 7 is the same as in the case of the first embodiment shown by way of example, except that in this case the crank rod 13 has been provided with an additional locking groove ll3e, with which a locking lever 20 can engage in the right-hand end position of the element 13. A return spring 21 pulls the locking lever 20 into the locking groove 13e. The plate 22 of a centrifugal governor is keyed onto shaft 1 at 24 and encloses therein a plurality of balls 23. As soon as the crank shaft 1 has reached a certain speed, the plate 22 is shifted to the right by balls 23, against spring 25, until the edge 22a reaches the locking lever 20 and moves it counter to its spring 21 to release lever 20 from locking groove l3e. Now the crank rod 13 can move to the left under the influence ofits spring 16a, to stop the stop member 12 and this commences the reloading procedure for the starter spring 7, in the manner as described previously.

A transverse peg 26 may be inserted into bushing 4 through the guide bushing 27 for manually operating the starter device. As a result of that, one will be able, in case starting spring 7 has been uncooked, to start the combustion engine via the crank shaft 1 by hand. The crank rod 13 is first completely pulled out (FlG. lb) after which the bushing 4 is turned clockwise. Alternatively, the crank rod 13 can be brought into the position according to FIG. la and then the starter spring 7 can be wound up in the same manner as described above by turning parts 1 and 4 in a clockwise direction; and the combustion engine can then be started subsequently by means ofthe loaded spring 7 as described above.

Many variations are possible within the spirit and scope of the invention. For example, the stopping of the carrier means may be accomplished by a brake, coupling or the like rather than the engagement of stop member 12 against crank rod 13. Also, as noted above, the differential drive may be a planetary gear drive rather than a friction roller drive. Also, other free running drives are known and may be employed in place of the ones described herein.

Thus, the present invention resides primarily in the arrangement including the two drive means between the control member and the shaft which may be rendered effective alternately such that the starting force is exerted through the free running drive and the reloading force is exerted through the differential drive. In this manner, and because ofthe suitable torques and accelerations of the masses, the transmission of forces during starting and reloading will be resolved in an optimum manner and hence there will be provided a starter device which will be suitable even for very large engines and/or for combustion engines having very strong vibrations.

Although the invention has been described in considerable detail with respect to a preferred embodiment thereof, it will be apparent that the invention is capable of numerous modifications and variations apparent to those skilled in the art without departing from the spirit and scope ofthe invention.

We claim:

1. A starter device for imparting rotational movement to a shaft comprising, a fixed housing member, a control member, a spring means adapted to be loaded to store energy and operatively connecting said control member to said housing member in such a manner that limited movement of said control member relative to said housing member is permitted, first and second coupling means operatively connecting said shaft and said control member, the first coupling means being a free running drive through which the control member drives the shaft in a first direction upon release of the stored spring energy, while also permitting free rotational movement of the shaft, relative to the control member, in said first direction, and said second coupling means being a differential drive positively engaging both the shaft and the control member continuously during both storing and releasing of the spring, and reloading means for causing said second coupling means to be driven by the said shaft to move the control member to load the spring means.

2. A starter device according to claim I wherein said control member is an annular collar surrounding said shaft and spaced therefrom to form an annular space, and wherein said first and second coupling means are mounted in said annular space.

3. A starter device according to claim 2 wherein said spring means comprises a spiral spring anchored at one end to the housing member and anchored at its other end to the collar, such that turning of the collar in a second direction opposite to said first direction winds the spring to store energy therein.

4. A starter device according to claim 3 including holding means for holding the collar in the position whereat the spring is wound.

5. A starter device according to claim 4 wherein said dif ferential drive comprises a plurality of planatary rolling elements in said annular space and positively engaging both said shaft and said collar.

6. A starter device according to claim 5 wherein said rolling elements include frictional outer surfaces which frictionally engage said collar and said shaft.

7. A starter device according to claim 5 wherein said rolling elements comprise a plurality of planatary gears positively engaging said collar and said shaft.

8. A starter device according to claim 5 including a carrier means for spacing said rolling elements from each other, and wherein said holding means comprises a crank rod mounted in said housing member and mounted to engage said collar to prevent rotation thereof.

9. A starter device according to claim 8 including a stop member connected to said carrier means, and said crank rod movable between at least first, second and third positions, whereat in the first position the crank rod prevents rotation of said collar, in second position the crank rod permits rotation of the collar and prevents rotation of said stop member and said carrier means, and in the third position the crank rod permits rotation of both said collar and said stop member, whereby when the crank rod is in said second position and the shaft is rotating in said first direction, the rolling elements rotate about their own axes to turn the collar in he second direction to load the s ring, and including resilient means for moving the crank ro from said second position to the said first position after the spring has been wound, and including means for moving the crank rod from said third position to the second position to commence reloading ofthe spring.

10. A starter device according to claim 9 wherein the last said means comprises a spring automatically operable immediately upon movement of the crank rod to said third position.

11. A starter device according to claim [0 including a damping means for delaying movement of said crank rod to said second position.

12. A starter device according to claim 11 wherein said damping means comprises a piston connected to the last said spring and mounted in a chamber in said housing member, and including a restricted opening leading from said chamber.

13 A starter device according to claim 9 wherein the last said mans comprises a governor device operable in response to turning of the said shaft at a predetermined speed for moving the crank rod to said second position.

14. A starter device according to claim 9 wherein, in said second position of the crank rod, a plurality of turns of the shaft are necessary to completely wind the spring.

15. A starter device according to claim 2 wherein said shaft is the end of an engine crank shaft, and includes a bushing fixed thereon and having a generally cylindrical outer contour which forms with said collar member the said annular space.

16. A starter device according to claim 15 wherein both said first and second coupling means are located in said annular space, and said free running drive comprises a set of rolling elements mounted between inner and outer surfaces which are rigidly connected to the bushing and the collar, respectively, said surfaces being shaped to prevent relative rotation between the surfaces in one direction and to permit relative rotation in the other direction.

17. A starter device according to claim 15 including manually operated means for engaging the bushing to turn the shaft to load the spring.

IS. A starter device according to claim 15 wherein said differential drive comprises a plurality of planetary rolling elements in said annular space and positively engaging both said shaft and said collar members.

19. A starter device according to claim 18 wherein said rolling elements include frictional outer surfaces which frictionally engage said collar and said shaft.

20. A starter device according to claim 18 wherein said rolling elements comprise a plurality of planetary gears positively engaging said collar and said shaft.

21. A starter designed for imparting rotational movement to a shaft comprising, a fixed housing member, a control member, a spring means adapted t be loaded to store energy and operatively connecting said control member to said housing in such a manner that limited movement of said control member relative to said housing member is permitted, first and second coupling means operatively connecting said shaft and said control member, the first coupling means being a free running drive through which the control member drives he shaft in a first direction upon release ofthe stored spring energy, and said second coupling means being a differential drive positively engaging both the shaft and the control member, a shift member for alternately rendering in operation one of said first and second coupling means, said shift member having at least a first setting position for setting in operation the first coupling means for starting said shaft by means of the loaded spring means, and a second setting position for setting in operation the second coupling means for reloading said spring means through the running movement ofthe shaft.

22. A starter device according to claim 21, wherein said shift member is located outside of the shaft axis and is provided with a hand setting knob. 

1. A starter device for imparting rotational movement to a shaft comprising, a fixed housing member, a control member, a spring means adapted to be loaded to store energy and operatively connecting said control member to said housing member in such a manner that limited movement of said control member relative to said housing member is permitted, first and second coupling means operatively connecting said shaft and said control member, the first coupling means being a free running drive through which the control member drives the shaft in a first direction upon release of the stored spring energy, while also permitting free rotational movement of the shaft, relative to the control member, in said first direction, and said second coupling means being a differential drive positively engaging both the shaft and the control member continuously during both storing and releasing of the spring, and reloading means for causing said second coupling means to be driven by the said shaft to move the control member to load the spring means.
 2. A starter device according to claim 1 wherein said control member is an annular collar surrounding said shaft and spaced therefrom to form an annular space, and wherein said first and second coupling means are mounted in said annular space.
 3. A starter device according to claim 2 wherein said spring means comprises a spiral spring anchored at one end to the housing member and anchored at its other end to the collar, such that turning of the collar in a second direction opposite to said first direction winds the spring to store energy therein.
 4. A starter device according to claim 3 including holding means for holding the collar in the position whereat the spring is wound.
 5. A starter device according to claim 4 wherein said differential drive comprises a plurality of planatary rolling elements in said annular space and positively engaging both said shaft and said collar.
 6. A starter device according to claim 5 wherein said rolling elements include frictional outer surfaces which frictionally engage said collar and said shaft.
 7. A starter device according to claim 5 wherein said rolling elements comprise a plurality of planatary gears positively engaging said collar and said shaft.
 8. A starter device according to claim 5 including a carrier means for spacing said rolling elements from each other, and wherein said holding means comprises a crank rod mounted in said housing member and mounted to engage said collar to prevent rotation thereof.
 9. A starter device according to claim 8 including a stop member connected to said carrier means, and said crank rod movable between at least first, second and third positions, whereat in the first position the crank rod prevents rotation of said collar, in second position the crank rod permits rotation of the collar and prevents rotation of said stop member and said carrier means, and in the third position the crank rod permits rotation of both said collar and said stop member, whereby when the crank rod is in said second position and the shaft is rotating in said first direction, the rolling elements rotate about their own axes to turn the collar in he second direction to load the spring, and including resilient means for moving the crank rod from said second position to the said first position after the spring has been wound, and including means for moving the crank rod from said third position to the second position to commence reloading of the spring.
 10. A starter device according to claim 9 wherein the last said means comprises a spring automatically operable immediately upon movement of the crank rod to said third position.
 11. A starter device according to claim 10 including a damping means for delaying movement of said crank rod to said second position.
 12. A starter device according to claim 11 wherein said damping means comprises a piston connected to the last said spring and mounted in a chamber in said housing member, and including a restricted opening leading from said chamber. 13 A starter device according to claim 9 wherein the last said mans comprises a governor device operable in response to turning of the said shaft at a predetermined speed for moving the crank rod to said second position.
 14. A starter device according to claim 9 wherein, in said second position of the crank rod, a plurality of turns of the shaft are necessary to completely wind the spring.
 15. A starter device according to claim 2 wherein said shaft is the end of an engine crank shaft, and includes a bushing fixed thereon and having a generally cylindrical outer contour which forms with said collar member the said annular space.
 16. A starter device according to claim 15 wherein both said first and second coupling means are located in said annular space, and said free running drive comprises a set of rolling elements mounted between inner and outer surfaces which are rigidly connected to the bushing and the collar, respectively, said surfaces being shaped to prevent relative rotation between the surfaces in one direction and to permit relative rotation in the other direction.
 17. A starter device according to claim 15 Including manually operated means for engaging the bushing to turn the shaft to load the spring.
 18. A starter device according to claim 15 wherein said differential drive comprises a plurality of planetary rolling elements in said annular space and positively engaging both said shaft and said collar members.
 19. A starter device according to claim 18 wherein said rolling elements include frictional outer surfaces which frictionally engage said collar and said shaft.
 20. A starter device according to claim 18 wherein said rolling elements comprise a plurality of planetary gears positively engaging said collar and said shaft.
 21. A starter designed for imparting rotational movement to a shaft comprising, a fixed housing member, a control member, a spring means adapted t be loaded to store energy and operatively connecting said control member to said housing in such a manner that limited movement of said control member relative to said housing member is permitted, first and second coupling means operatively connecting said shaft and said control member, the first coupling means being a free running drive through which the control member drives he shaft in a first direction upon release of the stored spring energy, and said second coupling means being a differential drive positively engaging both the shaft and the control member, a shift member for alternately rendering in operation one of said first and second coupling means, said shift member having at least a first setting position for setting in operation the first coupling means for starting said shaft by means of the loaded spring means, and a second setting position for setting in operation the second coupling means for reloading said spring means through the running movement of the shaft.
 22. A starter device according to claim 21, wherein said shift member is located outside of the shaft axis and is provided with a hand setting knob. 